The construction and related industries today install increasing amounts of tiles and related materials, with larger size materials becoming more popular and with more demand for finer detail in the finished product. The trend for larger size materials has created a vacuum for a precision saw that can cut all size workpieces but in particular, pieces 18 inches or larger, as well as cutting diagonals and corners on such pieces without damaging them. Since it's necessary to bring a saw on such jobs, it is also important that the saw be light enough to be carried by one or two men and that it not take up too much space. Therefore, there is a need for a lightweight, relatively inexpensive, precision cutting abrasive saw for large and small workpieces that exceeds the accuracy of the much heavier and costlier saws available on the market today.
Presently, many tile cutting machines incorporate mounting the workpiece on a roller and track sliding table, whereupon the table is pushed against a fixed abrasive saw. The most important disadvantage to these systems is that generally, the table rests by gravity unlocked to the tracks so that skewing of the table plane occurs relative to the plane of the cutting saw, hence uneven cutting. The present invention avoids this by orienting the carriage plane parallel to the saw cutting plane. Another disadvantage to these systems is that the rollers and tracks slide under the fixed saw accumulating tile dust particles. This produces grinding effects which wear out the rollers and tracks. Since there is no adjustable locking for the rollers and tracks, there is further decrease in cutting precision. The present invention mounts the tracking system above and away from the saw cutting path. Another obvious limitation to these systems is that half the table supports a non cutting area wasting half the machine and increasing half its weight. This also restricts the size of the workpieces that can be used. For larger workpieces it is necessary to cut through half the workpiece, remove the workpiece, rotate 180 degrees, secure, then cut again. Where these systems limit the length and width of a workpiece, the present invention limits only one dimension while the other dimension is open. For example, a 12 inch sliding table system requires a 12 inch non cutting area plus the saw cutting area plus the cutting through area, say another 12 inches, for a total of about 30 inches to cut a 12 inch workpiece. The other dimension will also be limited by the width of the table. With the same surface area as the 12 inch sliding table saw, the present invention will cut a 25.5 inch diagonal (or larger) of an 18 inch tile while the other dimension remains unhindered.
Other systems presently in use are abrasive saws that are mounted on a roller bearing(s) with said bearing(s) supporting said saw while rolling on a track for a cutting path. In their present form these systems have one main disadvantage: as the roller bearings tend to wear in a normal orientation, the saw tends to skew from side to side causing irregular cuts. This occurs when the plane of the roller bearing wear is perpendicular to the plane of saw cut. In the tool and die trade this is known as bell-mouth.
The present invention overcomes all these limitations by incorporating an adjustable locking, V-Tracking System, where the planes of the bearing wear and carriage are parallel to the plane of the saw cut so that carriage skewing will occur only in a vertical direction, thereby unaffecting the accuracy of the workpiece cut. Also, as the bearings wear, the adjustable locking bushings will compensate for wear.
The following prior art references typify the aforementioned table carriage systems:
U.S. Pat. Nos. 5,127,391 and 4,940,038 by O'Keefe: Tile and Marble Cutting Apparatus and Method
wherein the improvement comprises a motor support wherein the motor may be moved laterally on the table support between preselected cutting positions. PA1 said longitudinal means comprising a series of spaced freely turning rollers mounted to said parallel rails for rollingly supporting the work piece thereon and for permitting ease of movement of the workpiece toward and away from the abrasive saw. PA1 a table reciprocally mounted on said rails supporting said work to be cut and being movable in a generally horizontal direction toward and away from said saw blade from a retracted position in which said table and the work thereon is clear of said saw blade and a cutting position in which said saw blade cuts through said work as the latter is moved past said saw blade. PA1 an apparatus for adjustably supporting a cutting tool or the like and particularly relates to an adjustable four bar linkage mounted on a linear bearing for supporting a cutting tool. PA1 a tile cutting apparatus comprising a work table adapted to support a tile to be cut, a guide and support track located beneath and/or to one side of the top of the work table and parallel to said one side thereof, a carriage guided and supported by the track and a cut off saw supported at a predetermined height above the table by a cantilevered arm extending from the carriage.
U.S. Pat. No. 4,991,354 by Schweickhardt: Abrasive Saw Adjustable Workpiece Supporting Frame
U.S. Pat. No. 4,428,159 by Sigetich: Portable Direct Drive Abrasive Saw
The following prior art references typify the roller track systems:
U.S. Pat. No. 4,817,581 by Trentadue: Adjustable Support for Cutting Apparatus
U.S. Pat. No. 4,541,404 by Dols: Tile Cutting Apparatus